1. Field of the Invention
Conventional hinged doors swing open on hinges to accomplish closing and opening performances. To keep the door in place instead of closing after the door is opened, and to avoid powerful slamming when the door is closed automatically, it is a common practice to install a door closer for positioning and buffer effects.
2. Background of the Invention
A hinged door usually swings open or close on a hinge. To enable the door to fix in position without closing again by itself, and avoid powerful slamming, after the door is opened, the door body is generally installed with a door closer with positioning and buffer performances.
A regular door closer involves a tube unit in which is installed a shaft rod that moves in and out in relation to the tube unit. On the part of the shaft rod extending out of the tube unit is a positioning plate. The positioning plate matches an outside end of the tube unit, and can move on the rod unit. When the door is opened, the positioning plate stops between the shaft rod and one end of the tube unit, so the shaft rod could not automatically retract inside the tube unit, so that when the door is opened, the door can be positioned instead of closing on its own. To close the door, the stop plate must be moved or turned to disengage the stop function formed by the positioning plate on the shaft rod and the tube unit, so the door can be close automatically.
It is obvious that, however, when the door is to be positioned after the door is opened, the positioning plate must be adjusted, which could be inconvenient. Besides, the positioning plate can easily be dislocated from its original position by accidental impact, causing the door to close unexpectedly. Such inconveniences need improvement.